How does Medicare interact with group health insurance for individuals 65 or older, working for an employer with fewer than 20 employees?

When individuals aged 65 or older are still working and are covered by an employer's group health insurance, the interaction between Medicare and group health insurance largely depends on the size of the employer. For employers with fewer than 20 employees, Medicare becomes the primary payer. This means that Medicare pays first for healthcare expenses, while the group health insurance may provide secondary coverage.

In this scenario, because the employer has a small group plan (fewer than 20 employees), Medicare typically gains priority. As a result, when a covered individual receives medical services, Medicare will handle the initial payment and the group health insurance may only cover additional costs that the Medicare does not, if applicable.

This also reflects the regulation that when an employer has fewer than 20 employees, the group health plan is not mandated to cover eligible individuals over 65 the same way as it would if the employer had 20 or more employees, where the group plan would be the primary payer. This distinction is crucial for understanding how benefits coordinate when both Medicare and a group plan are involved.